Green Highway

Washington State plug-in vehicle charging stations along Interstate 5 are getting used more than twice as much as they were a year ago, the Associated Press says, citing a study from the Washington State Department of Transportation. In September, the state's 14 fast-charging stations along I-5 were collectively used 1,155 times, up from 528 sessions a year earlier. All told, those stations have been used more than 10,000 times since their installation last year.

Stations on other, less-traveled state routes are not doing as well, though, with some getting used as few as 10 times a month. The state has been working with the federal government to ensure a string of charging stations exist along the 580-mile stretch of I-5 spanning from the Oregon to Canadian borders. In Oregon, the state's 34 stations along I-5 have also been used about 10,000 times since last year.

The study reflects the fact that the Pacific Northwest is a plug-in happy place. With Washington State home to about 5,000 registered plug-ins, the state has about 380 publicly accessible charging stations, or about one for every 15,000 registered vehicles, according to the US Department of Energy. That compares to about 6,760 publicly accessible charging stations in the US, or one for every 37,000 registered vehicles.